1. Field of the Invention
This invention relates generally to a shaft adapter, and particularly to a shaft adapter for converting shaft diameters and varying shaft length in conjunction with fan assemblies employed with refrigeration units, and the like.
2. Description of the Prior Art
A problem arises with the maintenance of refrigeration units and similar systems that employ cooling and air circulating fans. When a motor or blade of such a fan must be replaced, it is generally impractical for a service man to maintain a complete stock of all the different motors and blades that may be encountered. Accordingly, it is not unusual for a service man to carry only a single model replacement motor and associated fans for the commonly encountered capacity fan assemblies. Another situation is encountered where only the motor or blade of a fan assembly need be replaced, and the shaft diameter and/or shaft length of the existing unit is different from the replacement fan motor or fan blade. Thus, it is desirable to have a shaft adapter which will permit the diameter of the shaft to be converted between that of the standard replacement motor and various other shaft diameters. Further, it is desirable to have a shaft diameter which can be readily varied in length to be mated with existing dimensions.
A shaft adapter is known which is made of a relatively hard steel and is attached loosely to a shaft of a fan motor so as to be secured on the motor shaft as by a set screw. This arrangement is undesirable because of the relative inflexibility in use of such an adapter, and because the manner of mounting the adapter on the fan motor shaft is subject to loosening as by vibrations, and the like. In addition, the adapter must be provided with a keyed portion for receiving a likewise keyed fan blade.